Frequently Asked Questions

Q. What is the Henry Knob site?

A. The Henry Knob site mined kyanite, a mineral that is a form of aluminum silicate often used as a material in industrial furnaces and also used to make tiles to keep space shuttles from burning up during re-entry. Mining for kyanite took place at a large pit quarry on the Henry Knob site from the 1950s to the 1970s. During the mining process, mined ore was ground up and kyanite was separated from the other minerals in the ore using a water slurry and was skimmed from the top. The leftover ground up waste rock and soil, called tailings, were dried in ponds and piles. Much of the tailings washed off the knob and formed the sandy areas to the west.

Q. Who owns the Henry Knob site now?

A.  A private owner owns Henry Knob itself, the main area of the former mine.  Although ABB never owned the mine or any of the property – it acquired a company that had owned it a decade prior to the purchase – ABB recently purchased the main tailings areas, across Henry Knob Road, to facilitate the cleanup.

Q. What is ABB's connection to the site?

A. A company called Commercialores mined the site during the 1950s and 1960s. Combustion Engineering bought Commercialores in 1965 then sold the site in 1971. Since then, there have been several property owners. ABB bought Combustion Engineering in 1990 but never owned the property or managed any mining operations at the Henry Knob site.

Q. I wanted public water, why did you choose wellhead treatment instead?

A. As part of the environmental cleanup at Henry Knob, ABB submitted to EPA an Engineering Evaluation/Cost Analysis (EE/CA) report for possible groundwater remedies in March 2012. ABB and EPA recommended extending public water service from Clover. After EPA conducted a public meeting and public comment period on the report and the preferred remedy, ABB met with affected landowners and offered agreements to cover property access, construction and service. After all property owners responded, Clover officials determined that an insufficient number of homeowners accepted, making the extension of a public water system technically impractical. In the summer of 2013, EPA approved residential well treatment systems as the next best remedy.

Q. What is ABB offering?

A. For the homes whose groundwater tested above the Removal Action Level (RAL) presented in the EE/CA for mine-related manganese and/or cobalt, ABB will cover the cost of design, installation, testing and upkeep of the well treatment system. For the remainder of the homes in the affected area that do not have concentrations above the RAL, ABB will cover the cost of design and installation of the well treatment system.  ABB will not cover upkeep or maintenance.  ABB will conduct periodic testing, and if your home ever exceeds the RAL for mine-related impacts, we will cover upkeep and maintenance at that time. 

Q. If I accept the offer, will I have to pay any expenses related to connecting the treatment system to my plumbing?

A. ABB will pay all costs to connect the treatment system to your plumbing. 

Q. Why wasn’t the community water option chosen?

A.  Two forms of water service were considered as part of the study: public water, which refers to connecting to the Clover water services, and community water, which refers to a community-owned and managed water treatment system. The community water option presents two major challenges: finding an adequate lake, pond, river or groundwater well to produce sufficient volume of water, and the need for an elaborate water treatment system similar to what municipal governments provide. In light of these challenges, treatment of individual residential wells was seen as a better solution and quicker to implement. 

Q. Who is being offered the wellhead treatment?

A. Property owners, not tenants, who have homes on their property within the affected area. This area consists of 47 parcels and approximately 30 homes. Some parcels are undeveloped and do not have a home located on them. Of the 30 homes, only six had wells whose water tested above the Removal Action Level (RAL) presented in the EE/CA for mine-related manganese and/or cobalt. All parcels of land are in the immediate vicinity, less than a half mile radius, of Henry Knob. Treatment systems are being offered to all properties with homes located within the affected area, a zone where groundwater impacts exist now or are possible in the near future.

Q. How was the red line boundary, the affected area, determined?

A. The “affected area” includes property where groundwater is impacted now or has the potential to be affected in the near future.  It was defined based on the data collected and evaluated during the Remedial Investigation (RI) at the site. RI data was collected from groundwater monitoring wells and selected private residential wells located as far away as 1.2 miles from the former mine. Several rounds of laboratory tests were conducted on water samples from test wells and residential wells. The results were used to evaluate and define areas where groundwater had mine-related impacts and areas where it did not, using a specific geochemical signature found in the groundwater analytical results. Lines were drawn between the wells with no impacts from mining (clean boundary wells) to define the affected area. Two metallic elements of concern – manganese and cobalt— were found in six wells in the affected area above the RAL presented in the EE/CA. These are natural elements, like iron, that are good for us in a healthy diet, but raise risk questions when consumed in high doses. Because manganese is common in groundwater in the Carolinas, the geochemical signature was used to determine where concentrations possibly increased due to mining operations. 

Q. What is manganese?

A. Manganese is a naturally occurring metal. Manganese, like iron and aluminum, is found in minerals that occur in rock, soil and water. Manganese is an essential trace nutrient necessary for all forms of life and can be found in a variety of foods we eat every day.

Q. Is manganese in drinking water a health risk?

A. There is no conclusive scientific answer to this question, so ABB is advising people with well water exceeding the study’s risk standards to continue drinking bottled water until a groundwater remedy is in place. Manganese, like iron, is a natural element that we need in a healthy diet. However, regulatory agencies have not decided how much above the normal daily intake poses a risk, or if it poses a risk at all. Regulatory agencies have concluded it does not cause cancer, but there are studies showing neurological problems from heavy exposure, such as concentrated levels of exposure to manganese vapors in industrial settings, like smelters. Even at these levels, though, government agencies have not indicated if there is, or is not, a risk of adverse health effects from drinking water with manganese in it. The best information about manganese can be found on the Agency for Toxic Substances and Disease Registry (ATSDR) website:

EPA’s information on manganese:

  • The EPA has set a secondary drinking water standard for manganese of 0.5 milligrams per liter (mg/L). Secondary drinking water standards are provided by EPA as a guideline to assist public water systems to account for aesthetic considerations like taste, color and odor. From the EPA’s website: “These contaminants are not considered to present a risk to human health at the secondary maximum contaminant level.”

Q. What is being done about the tailings areas and the mine pit?

A. The focus of the ABB team has been to get a groundwater solution quickly. Now that the remedy has been selected, ABB is offering agreements to cover well treatment systems. ABB is also is moving on soils and surface water work. ABB has started conducting tests on the soils to help with study and design of possible remedies, such as revegetation, capping, and removal or treatment alternatives.

Q. Do soils and gardening present health risks?

A. It is safe for children and wildlife to be in contact with the soils, however, some people might get skin rashes with extended direct contact. It is also safe to use the water for gardening. The tailings areas, the soils, will likely be treated or revegetated in the future, so it is important that people not trespass and disturb these areas.

Q. Why is the process taking so long?

A. ABB understands public impatience with the process, as these studies and remedies do take many years. Although the Henry Knob site is not a Superfund site, EPA requires ABB to follow the Superfund process as ABB performs its investigation and remediation. This involves extensive sampling, testing and analysis, as well as formal and thorough documentation in reports according to specific EPA guidelines and regulations. This program is moving along as fast, if not faster than similar sites.

Q. Who can I talk to if I’m unhappy with how things are proceeding?

A. You can contact Barry Dillon at ABB,